Biology: The Study of Life
Natural Selection
Natural Selection • “Survival of the Fittest” – The organism that is best adapted for an environment will survive and reproduce – When they reproduce the successful genetics are passed to the next generation – The environment selects what is successful
Natural Selection • Camouflage – concealment by means of disguise • Preying Mantis
Natural Selection • Mimicry – Organism resembles another organism • Batesian – Non-poisonous organism mimics a poisonous organism » Coral snake and King snake
• Mullerian – Two poisonous organisms mimic each other » Monarch and Viceroy
Natural Selection • Desert hare vs. Arctic hare – Ears – Fur Color – Foot Size
Natural Selection • Darwin’s Finches
Natural Selection • Directional Selection – One of the extreme traits is more successful
Natural Selection • Disruptive Selection – The two extremes of the population are successful
Natural Selection • Stabilizing Selection – Average traits are more successful than the extreme traits
Natural Selection • Sexual Selection – An organism is selected for breeding based on its traits • Courtship Behavior – Peacock hen selecting a male with big, bright tail feathers – A female Brower bird selects its mate base on the quality of the Brower the male makes – Bird songs
Artificial Selection • Directed by humans not the environment • Breeding beef cattle to produce high quality meat • Breeding of plants to make high quality fruit • Breeding dogs to meet human likes
Natural Selection • “Survival of the Fittest” – The organism that is best adapted for an environment will survive and reproduce – When they reproduce the successful genetics are passed to the next generation – The environment selects what is successful
Natural Selection • Camouflage – concealment by means of disguise • Preying Mantis
Natural Selection • Mimicry – Organism resembles another organism • Batesian – Non-poisonous organism mimics a poisonous organism » Coral snake and King snake
• Mullerian – Two poisonous organisms mimic each other » Monarch and Viceroy
Natural Selection • Desert hare vs. Arctic hare – Ears – Fur Color – Foot Size
Natural Selection • Darwin’s Finches
Natural Selection • Directional Selection – One of the extreme traits is more successful
Natural Selection • Disruptive Selection – The two extremes of the population are successful
Natural Selection • Stabilizing Selection – Average traits are more successful than the extreme traits
Natural Selection • Sexual Selection – An organism is selected for breeding based on its traits • Courtship Behavior – Peacock hen selecting a male with big, bright tail feathers – A female Brower bird selects its mate base on the quality of the Brower the male makes – Bird songs
Artificial Selection • Directed by humans not the environment • Breeding beef cattle to produce high quality meat • Breeding of plants to make high quality fruit • Breeding dogs to meet human likes
